Non-Random Variation

Random Variation: Random variation refers to natural variability or differences that occur in a population due to chance, without any systematic influence.

Confounding Variable: A confounding variable is an extraneous factor that affects both the independent and dependent variables, leading to spurious associations between them.

Bias: Bias occurs when there is a consistent deviation from true values or an over/underestimation of certain outcomes due to flaws in study design or data collection methods.